Accuracy of orbits for GPS atmospheric water vapour estimation

A major error source in GPS measurements for precise height applications is the wet path delay due to tropospheric water vapour. It has recently been demonstrated that the tropospheric Zenith Wet Delay (ZWD) can be estimated using the GPS data itself and converted to equivalent Integrated Water Vapo...

Full description

Saved in:
Bibliographic Details
Published in:Physics and chemistry of the earth 1998, Vol.23 (1), p.119-124
Main Authors: Dodson, A.H., Baker, H.C.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A major error source in GPS measurements for precise height applications is the wet path delay due to tropospheric water vapour. It has recently been demonstrated that the tropospheric Zenith Wet Delay (ZWD) can be estimated using the GPS data itself and converted to equivalent Integrated Water Vapour (IWV) content with little additional uncertainty (where 1 kg/m 2 IWV is equal to 1 mm Integrated Precipitable Water Vapour, and equates approximately to 6.5 mm ZWD). One of the major factors in achieving accurate estimates on a near real time basis (less than a few hours) is the availability of reliable, accurate orbits. Tests have therefore been performed investigating the accuracy of GPS water vapour estimates using a number of current, freely available, rapid and predicted orbits in comparison to the IGS precise ephemeris. Initial results indicate that rapid orbit water vapour estimates compare to better than 1 kg/m 2, and predicted orbit water vapour estimates at 1–6 kg/m 2 level, with significant improvement in estimates when they are differenced.
ISSN:0079-1946
1879-3568
DOI:10.1016/S0079-1946(97)00253-X